Remove reference of NetworkAgent#unwanted()

This is hidden, use onNetworkUnwanted instead.

Test: TH
Bug: 182963397
Change-Id: I4e80a75d25cfd9ffc07aa219fff5a2604eb307f2

services/core/java/com/android/server/connectivity/Vpn.java

@@ -1262,7 +1262,7 @@ public class Vpn {
         mNetworkAgent = new NetworkAgent(mContext, mLooper, NETWORKTYPE /* logtag */,
                 mNetworkCapabilities, lp, VPN_DEFAULT_SCORE, networkAgentConfig, mNetworkProvider) {
             @Override
-            public void unwanted() {
+            public void onNetworkUnwanted() {
                 // We are user controlled, not driven by NetworkRequest.
             }
         };

services/core/java/com/android/server/vcn/VcnGatewayConnection.java

@@ -1444,7 +1444,7 @@ public class VcnGatewayConnection extends StateMachine {
                             new NetworkAgentConfig.Builder().build(),
                             mVcnContext.getVcnNetworkProvider()) {
                         @Override
-                        public void unwanted() {
+                        public void onNetworkUnwanted() {
                             Slog.d(TAG, "NetworkAgent was unwanted");
                             teardownAsynchronously();
                         }